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Investment in ATC | 3 Months Ended
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Mar. 31, 2016
Equity Method Investments and Joint Ventures [Abstract] |
Investment in ATC [Text Block] | INVESTMENT IN ATC Our wholly-owned subsidiary, ALLETE Transmission Holdings, owns approximately 8 percent of ATC, a Wisconsin-based utility that owns and maintains electric transmission assets in parts of Wisconsin, Michigan, Minnesota and Illinois. We account for our investment in ATC under the equity method of accounting. As of March 31, 2016, our equity investment in ATC was $128.6 million ($124.5 million at December 31, 2015). In the first three months of 2016, we invested $1.2 million in ATC, and on April 29, 2016, we invested an additional $0.4 million. We expect to make additional investments of approximately $4.6 million in 2016.
ALLETE’s Investment in ATC |
Millions |
Equity Investment Balance as of December 31, 2015 |  | $124.5 |
Cash Investments | 1.2 |
Equity in ATC Earnings | 4.8 |
Distributed ATC Earnings | (1.9 | )
Equity Investment Balance as of March 31, 2016 |  | $128.6 |

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- Definition The entire disclosure for equity method investments and joint ventures. Equity method investments are investments that give the investor the ability to exercise significant influence over the operating and financial policies of an investee. Joint ventures are entities owned and operated by a small group of businesses as a separate and specific business or project for the mutual benefit of the members of the group. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=49116238&loc=d3e32847-111569 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=49116238&loc=d3e32787-111569 + Details
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